Renewable tip hammer



Aug. 1, 1961 F. E; TRUD EAU 2,994,486

RENEWABLE TIP HAMMER Filed Nov. 2, 1959 2 Sheets-Sheet 1 FIG! INV EN TOR.

FRANCIS E. TRUDEAU Aug. 1 F. E. TRUDEAU RENEWABLE TIP HAMMER 2 Sheets-Sheet 2 Filed NOV. 2, 1959 INVENTOR. FRANCIS E. TRUDEAU United States Patent 2,994,486 RENEWABLE TIP IhtMlMER Francis E. Trudeau, Chicago Heights, 11]., assignor to Poor & Company, Chicago 4, 11]., a corporation of Delaware Filed Nov. 2, 1959, Ser. No. 850,325 Claims. (Cl. 241--197) This invention relates to an improvement in hammers for reduction mills, pnlverizing mills or the like and which may either rotate continuously in one direction, or, which on the other hand, are reversible.

One of the objects of the invention is to provide a hammer with a sturdy and substantial one piece shank and a removable tip, both of which lend themselves to simplicity of embodiment, economy of manufacture, and long life in use. Moreover, the structural features are such as to provide positive retainment between the tip and the shank while in use, and at the same time rendering the tip removable either for purposes of renewal or to be reversed. A shank made in one piece has the advantage over the usual split shank because it provides a more uniform bearing on the shaft and there are no parts between which material can wedge to cause binding between the discs supporting the shaft. Thus, a onepiece shank is always free to swing between the discs, and the contacting faces always remain in proper relation to each other.

Another object of the invention is to provide a reversible double impact faced tip wherein up to seventy-five percent of the weight of the body of the tip can be worn away and still leave adequate metal around interfitting shank surfaces to protect them from wear, thereby keeping the shanks useful for replacing Worn tips with new tips for a greater period of time than is the case with the average hammer. Another advantage is that the present tip can be changed in the mill without removing the shanks, thereby considerably shortening the downtime of the mill.

A further object is to provide the hammer whose shank and tip have novel interfitting parts which may be readily and firmly wedged together.

With the above and other objects in view, which will more readily appear as the nature of the invention is better understood, the same consists in the novel construction, combination and arrangement of parts hereinafter more fully described, illustrated, and claimed.

A preferred and practical embodiment of the invention is shown in the accompanying drawings, in which:

FIGURE 1 is a perspective view of the shank and tip, separated to better illustrate the construction and the manner in which the shank and tip are assembled.

FIGURE 2 is a side elevation of the assembled tip.

FIGURE 3 is an end elevation, partly in section, of the construction shown in FIGURE 2.

Similar reference characters designate corresponding parts in the several figures of the drawings.

Basically the invention includes a shank S and a tip T which are separably interlocked, not only facilitating manufacture and assembly, but also, when necessary, permitting the tip to be renewed or replaced, or even turned around to present a fresh impact face if it is not used in a reversible mill. Moreover, the arrangement described permits making the shank out of one alloy and the tip out of a harder and more wear-resistant alloy because, as is well known, the tip bears the brunt of the impact of breaking up rock or other material.

Referring first to the one piece shank S, it will be observed that the same is provided with a transverse opening 1 to enable it to be mounted on the mill shaft in the usual manner. The shank includes a front wall 2, an opposite wall 3 which could be the rear wall if 'home, are bent down to lock the keys in place.

Patented Aug. 1, 1961 the mill is turning in a direction where 2 would be the front wall. Or, if the shanks are reversed on the shaft or the mill itself is reversible then the designated front and rear walls would also be reversed. The lower end portions of the walls 2 and 3 are provided with angular arched recessed portion x and each wall is also provided with wedge receiving openings W0 and WO'. Also, the shank is provided with opposite side walls 4 and 5, each terminating in the downwardly extending ears 6 and 7 whose edge portions are of substantially compound arcuate formation S to interfit with similar mating portions of the tip T as will presently appear. The shank S is further provided with an interior cavity or mortise accessible from the lower end of the shank between the ears 6 and 7.

The shank cavity, designated generally as 8, has the opposite side walls 9 and 10 which are respectively provided with reversely tapering wedge-shaped partial grooves 9a and 10a for receiving reversely related wedge keys W and W, passing through openings W0 and WO respectively, to enter said partial grooves and the partial complementary related grooved surfaces 11 and 12 formed by fillets between the web 13 and head 14, when the tenon T is placed in the mortise cavity 8. A distinctive feature of the invention is that the arrangement described placed the wedge keys in longitudinal shear.

The tip T includes what may be conveniently termed a front impact face 15 and a rear impact face 16 both of which are substantially coextensive with the width of the walls 2 and 3 of the shank when the tip and shank are assembled. In addition, the tip also includes the opposite side walls 17 and 18 which, as shown in FIG- URE 3, are substantially coextensive in Width with the side walls 4 and 5 of the shank, but, as will be clear from FIGURE 1, the upper portion of the tip body extending to either side of the web 13 is provided with depressed socket portions 6a and 7a for receiving the mating profiles of the downwardly projecting ears 6 and 7. Moreover, the upper portions of the impact faces 15 and 16 of the tip are provided with angularly disposed key portions y which mate with the recesses x to absorb lateral thrusts on the tip.

As will be apparent from FIGURES 2 and 3, when the shank S and tip T are assembled, the wedge keys W and W fit into the openings W0 and W0 of the face 2 and the similar openings of the opposite wall 3 to firmly engage in the complementary tapered grooves 9a-10a, and 1112 respectively, to firmly and strongly interlock the whole tip with the shank. 'I'he shank 13 and head 14 of the tenon T have a sufliciently loose fit in the cavity 8 to enable the Wedge keys, when driven home, to draw the tip tightly to the shank both laterally and longitudinally of the tip and draw x-y and 66a, 77a solidly together.

It will, of course, be understood that the small ends of the tapering wedge keys W and W, after being driven If it becomes necessary to remove the tip for bringing a new impact face into play, or completely substitute a new tip, then the bent end of the wedges can be straightened enough to withdraw them to release the tip and also to enable them to be reused.

It will now be seen that the present construction provides an extraordinarily sturdy and substantial construction which will stand much abuse and will provide maximum wear and consequent efficiency from the standpoint of installation, maintenance, and repair to the end that the mills using the invention will have maximum productive time on an economical basis.

I claim:

1. A hammer for reduction mills, comprising, in combination, a unitary shank body presenting front and rear walls and opposite side walls, said body having a transverse shaft receiving opening at its upper end penetrating its side walls and a mortise cavity opening at its lower end and disposed at right angles to said opening, the opposite sides of the cavity having partial wedge receiving grooves opening at the said front and rear walls of the shank and lower end of the body in the zone of the opposite side Walls of the shank presenting downwardly extending abutment shoulders, and a tip for the shank and having front and rear impact faces and side faces for substantial registry with the corresponding said front and rear walls and side walls of the shank and defining an impact body, a tenon on the tip for entering said mortise cavity on the shank and also having partial wedge receiving grooves on its opposite sides complementing the mating partial grooves on the side walls of the cavity, and wedges entering said registering complementary grooves to lock the tip to the Shank and cause the portions of the tip at each side'of the tenion to engage the said abutment shoulders on the body, said wedges being in longitudinal shear.

2. The combination defined in claim 1, wherein the mortise cavity is closed at the front and back of the tip and has parallel side walls, and the tenon on the tip is of substantially T-shaped cross section with its shank and head portion providing fillets at their junction forming partial grooves to cooperate and register with the partial wedge receiving grooves on side walls of the cavity.

3. The combination defined in claim 1, wherein, the mortise slot has spaced parallel side walls and the tenon on the tip is of substantially T-shaped cross section with its web and head portion providing fillets at their junction to constitute partial wedge receiving grooves, the shank and head being of less width than the slot to provide tolerances for assembling the shank and tip, and said head being of less depth than the slot to provide tolerance to insure the wedges exerting maximum gripping force between the tip and body.

4. As an article of manufacture, a reversible tip for the shanks of hammers used in hammermills, comprising, a body having opposite selectively useful impact faces flanked by side faces, and a tenon disposed medially of the side faces and substantially parallel thereto, said tenon including a web terminating in a head projecting above said impact faces and having oppositely tapering key contacting surfaces.

5. As an article of manufacture according to claim 4, wherein, the length of the web is less than the distance between said impact surfaces and extends equally on either side of a plane equidistant between said impact faces.

References Cited in the file of this patent UNITED STATES PATENTS 1,630,021 Lucas May 24, 1927 1,940,116 Brooks Dec. 19, 1933 2,183,880 Brooks Dec. 19, 1939 2,950,066 Smith Aug. 23, 1960 FOREIGN PATENTS 554,677 Germany July 9, 1932 725,652 Germany Sept. 26, 1942 

